Montana Judge Denies Challenge to Cannabis DUI Law

A Montana district judge has denied an attorney's challenge to the constitutionality of the state's DUI limit for cannabis. Public defender Gregory Paskell requested a constitutionality review of the state marijuana DUI law, arguing that there is no hard science supporting the legal threshold of 5ng/mL blood content as a definitive level of impairment. Paskell's client, 20-year-old Kent Roderick Jansen, was charged with vehicular homicide while under the influence after crashing into a motorcycle in March 2016, killing the rider.

A blood test showed that Jansen had 19ng/mL of THC in his blood at the time of the accident. Paskell argued that the charges against Jansen should be dismissed, citing a 2016 report from the AAA Foundation for Traffic Safety. This report argued against setting a specific threshold for cannabis impairment because individuals have widely variable tolerances to the drug.

District Judge Gregory Todd denied the request for a constitutionality review, arguing that although the science behind the impairment threshold limit is not exact, the goal of the DUI law is to reduce impaired driving overall. "Currently there may be no method for precisely measuring the distracting effects of THC on a person," Todd wrote. "But it is scientifically proven that THC had major psychoactive effects on people, and driving while under its effects poses a major risk to the driver and the public."

Jansen will now stand trial for the vehicular homicide charges on August 30th.